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FR Matuschka TW Schinkel B Klug A Spielman D Richter 《Canadian Metallurgical Quarterly》1998,64(8):3089-3091
To define conditions promoting inherited infection by Lyme disease spirochetes in Ixodes ticks, we variously infected ticks with Borrelia afzelii and examined their progenies by dark-field microscopy, immunofluorescence, PCR, and serial passage. No episode of inherited infection was evident, regardless of instar or gender infected or frequency of exposure. We suggest that these spirochetes rarely, if ever, are inherited by vector ticks. 相似文献
23.
Kalinnik Natalia Kiesel Robert Rauber Thomas Richter Marcel Rünger Gudula 《The Journal of supercomputing》2021,77(4):3484-3515
The Journal of Supercomputing - Scientific application codes are often long-running time- and energy-consuming parallel codes, and the tuning of these methods towards the characteristics of a... 相似文献
24.
Otto Richter Thomas Schmidt Hand Büning-Pfaue und Dietrich Reinhardt 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1988,187(2):130-136
Zusammenfassung Es werden pharmakokinetische Modelle angegeben, um den Konzentrationsverlauf von Arzneimittelrückständen im Menschen zu berechnen, die mit der Nahrung aufgenommen werden. Dabei lassen sich zwei Kompartimentmodelle für die Kinetik in der Nahrung und im Menschen koppeln: Das erste System liefert die Anfangswerte (bzw. eine Folge von Anfangswerten) für das zweite System. Das Modell wird auf die Übertragung von Chloramphenicol durch Speisefische auf den Menschen und auf die Übertragung von Theophyin durch die Muttermilch auf gestillte Säuglinge angewendet. Durch Einführung einer günstigsten und ungünstigsten Parameterkombination werden Grenzverläufe für die Blutspiegel berechnet, die als Grundlage einer Rückstandsbewertung dienen können.
Residues of active substances following the consumption of contaminated food —Status report on the evaluation of residues based on two drugs
Summary Pharmacokinetic models are presented for the computation of time courses of blood levels of drugs in man following the consumption of contaminated food. Mathematically, two linear systems of differential equations are set up for the donor organism (e.g., trout) and for the recipient, (e.g., man), where the first system generates the initial conditions for the second. Models of this kind are applied to the transfer of chloramphenicol to man via carp and trout (which had previously been administered this drug) and to the transfer of theophylline to infants via breast milk. Limiting concentration profiles are computed by constructing the most favourable and most adverse combinations of parameters with respect to drug elimination in both the donor and recipient organism.相似文献
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Dirk Anderheiden Otto Brenner Doris Klee Robert Kaufmann Horst A. Richter Christian Mittermayer Hartwig Hcker 《大分子材料与工程》1991,185(1):109-127
Different polyurethanes were synthesized by varying the diol as well as the diisocyanate components and chain extenders. Polyurethanes with OH-groups were obtained by photo- and thermoinitiation of the radical polymerization of hydroxy alkyl acrylates in the presence of the polyurethanes. The polymers were evaluated with respect to their biocompatibility by measuring the cell spreading, the rates of DNA- and protein synthesis and the swelling behaviour. The differences in the surfaces and the bulks between the selected basic polyurethane and the functionalized modification were determined and characterized by XPS, FTIR-ATR and 13C-FT-NMR-spectroscopy. The mechanical data of Tecoflex EG 60D® and Pellethane 2363–80AE® were compared with the data of the synthesized polyurethanes. 相似文献
27.
The characterization of thin, selectively imprinted films of nylon‐6 was performed. Amino acids were used as template molecules. Spin‐cast films were prepared with sizes ranging from 2 μm to 300 nm, depending on the nylon and template concentration in the casting solution. The morphological characteristics of the film surface were examined by atomic force microscopy, and the structure within the films was observed by freeze‐fracture scanning electron microscopy. The film activity was clearly coordinated with the appearance of nanometer‐sized pores both on the surface and within the film. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2919–2926, 2006 相似文献
28.
Ekkehard H. Lutz 《Journal of the American Ceramic Society》1994,77(5):1274-1280
Plasma spraying, originally a surfacing technology used for ceramic coating of metal and nonmetal substrates, is suitable for producing large, full ceramic bodies, such as plates and tubes, in situ to almost the desired dimensions; i.e., conventional methods of designing by molding and casting green bodies followed by sintering are not required. These "plasma ceramics" exhibit characteristic mechanical and thermomechanical properties. Their porous laminar grain structure results in low E -modulus and strength, and in extreme thermal shock resistance, which is enhanced by the comparably high fracture resistance of the material. Because of these properties and their low hardness, plasma ceramics can be easily machined with almost conventional methods of metal processing. 相似文献
29.
In the field of flue gas cleaning, active coke plays an important role as adsorbant and catalyst. In the temperature range usually prevailing downstream of the air preheater of power plants, SO2 becomes adsorbed on carbonaceous materials and in a consecutive step is catalysed by the carbonaceous surface and converted to sulphuric acid. The quality demands for a cyclic regenerative process for SO2 removal are fulfilled by the active coke which is used in the BF-process. The same active coke catalyses the reaction of NO with NH3 to N2 and steam. This is the basis for processes for simultaneous SO2 and NOx removal. By the addition of ammonia the SO2 removal by active coke is improved. Two processes are described and results from the laboratory and from the demonstration plant for the BF-process are presented. These show that SO2 removal efficiences exceed 95% and NO conversions of > 80% can be realized without problems. The cost of the processes using active coke with ammonia addition are comparable with those of wet flue gas desulphurization processes without any additional equipment should NO have to be removed. 相似文献
30.
In this paper, we present an invariant‐set‐based method for actuator and sensor fault detection and isolation in Lure systems. The Lure plant is controlled by an observer‐based feedback tracking controller, designed for the nominal (fault‐free) system. Suitable residual signals are constructed from measurable system outputs and estimates associated with the nominal observer. Faults are diagnosed by online contrasting the residual signal trajectories against sets of values that the residuals are shown to attain under healthy or faulty operation. These values are obtained via set‐invariance analysis of the system closed‐loop trajectories. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献